Slurry pump and transmission bearing coupling dynamics fault simulation method

Abstract

The invention provides a slurry pump and transmission bearing coupling dynamics fault simulation method. The method comprises the following steps of: establishing finite element models of a slurry pump impeller, a volute, a mixed fault, a transmission bearing inner ring, a transmission bearing outer ring and a mixed fault; fluent software is used for simulating the slurry pump in each healthy state, and the influence of pump shaft axial force generated by fluid under different inlet speeds on the dynamic characteristics of a transmission bearing, the stress change rule and the lift change rule of the slurry pump are analyzed. Axial force generated by pump fluid is coupled to a transmission bearing, then ANSYS LS-DYNA and Fluent are used for axial force coupling simulation, and the vibration characteristics and the action mechanism of the axial force of the slurry pump on the transmission bearing in different health states are analyzed. Compared with the prior art, the effective slurry pump fault simulation analysis method is provided, the influence and stress distribution of the axial force generated by the slurry pump fluid on the vibration characteristics of the transmission bearing and the hydraulic characteristics of the slurry pump body are analyzed, and research on slurry pump fault diagnosis is assisted.

Description

Technical Field

[0001] The present invention relates to the field of fluid machinery, and in particular to a slurry pump and a transmission bearing coupling dynamics fault simulation method. Background Art

[0002] The slurry pump is a common mechanical power equipment in fluid machinery. The slurry pump is often used in sewage discharge operations and other industrial sites. Its main components include volute, impeller, front and rear cavity cover plates and other flow-through parts. In addition, the transmission end bearing plays a supporting role in the slurry pump transmission system, bearing the axial and radial loads. Its failure often occurs in complex environments. In this case, it will cause huge losses to industrial production. In addition, damage to the pump's flow-through parts such as the impeller volute and other key components will also affect the hydraulic performance of the slurry pump, thereby reducing the service life of the pump. The industrial site generally performs hydraulic performance tests on the slurry pump, but when the pump fails, it is not known what specific type of failure the pump has. The present invention simulates slurry pumps in different health states through a simulation method, analyzes it at different flow rates, compares the head change law of slurry pumps in different health states, and calculates the pump shaft axial force generated by the fluid medium at the shaft end of the pump shaft. The axial force of the pump shaft has a certain influence on the dynamic vibration characteristics of the transmission bearing in different health states. It is very important to find the change law of the hydraulic characteristics of the slurry pump in different health states and the influence law of the axial force generated by the fluid medium on the dynamic characteristics of its transmission bearing. It can not only analyze the influence law of the inlet speed parameters of the slurry pump fluid medium on the hydraulic characteristics of the slurry pump in different health states, but also analyze the influence law of the axial force generated by different parameter combinations on the dynamic characteristics of the slurry pump transmission bearing, so as to achieve a certain auxiliary role in the fault analysis of the slurry pump.

[0003] At present, the research on fluid mechanics of slurry pumps uses discrete element method to study the influence of parameters such as number of blades, blade breakage, inlet flow rate on the hydraulic characteristics of slurry pumps, or only studies the dynamic vibration characteristics of pump shaft bearings, or studies the influence of slurry pump pressure pulsation characteristics and slurry concentration on slurry pump vibration. The influence of the axial force generated by the fluid medium on the coupling effect of the slurry pump bearings is not considered, and the hydraulic performance test of the pump is verified by using a small pump in the laboratory. Although the above method is reliable, it does not consider the influence of the axial force generated by the slurry pump fluid medium on the pump shaft on the transmission bearing, and most experiments are conducted when the pump is in good condition. However, in actual production, when the flow-through parts of the slurry pump fail, its hydraulic characteristics are different from the working conditions of the pump in a healthy state, and when the slurry pump fails, more pump shaft movement and axial force may be generated. This has a certain impact on the transmission bearing. Since most of the tested slurry pumps are used for production needs, the laboratory uses good slurry pumps. However, when the flow-through components of the pump fail, the hydraulic characteristics of the pump and the axial force changes generated at the pump shaft end are inconsistent. The test pump cannot be damaged in a short time, and it cannot be discovered and replaced in time after damage. The impact and effect of the axial force generated by the slurry pump failure on the transmission end bearing are often unable to be verified in real time.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The main purpose of the present invention is to provide a method for simulating the coupled dynamic faults of a slurry pump and a transmission bearing, aiming to provide an influence of the hydraulic characteristics of a slurry pump and the different axial forces generated by the fluid medium on the dynamic characteristics of the transmission bearing under different health conditions of the slurry pump and different health conditions of the pump transmission bearing, so as to provide a simulation analysis method for fault diagnosis of the slurry pump.

[0006] To achieve the above object, the present invention provides a slurry pump and transmission bearing coupled dynamic fault simulation method, the method comprising the following steps:

[0007] Step 1: According to the parameters and dimensions of the slurry pump and its transmission bearing, a three-dimensional slurry model of impeller failure, volute failure, and mixed failure, as well as a three-dimensional solid model of the transmission bearing of inner ring failure, outer ring failure, and mixed failure are established.

[0008] Step 2: Use the ANSYS-ICEM module to mesh the transmission bearings of the slurry pump in different health states and establish an explicit dynamic finite element model of the bearing.

[0009] Step 3: Extract the fluid domain of the three-dimensional model of the slurry pump in different health states and name the fluid domain. Then, mesh the fluid domain model and establish a finite element model of the slurry pump.

[0010] Step 4: Use the ANSYS-LSDynamic pre-processing module to perform explicit dynamic analysis on the transmission end bearing, define simulation parameters such as simulation time and boundary conditions, solid materials, load conditions, and set vibration monitoring points.

[0011] Step 5: Use the fluent software to perform fluid mechanics analysis on the finite element model of the slurry pump in different health states, set the liquid medium and solution algorithm of the slurry pump, define other simulation parameters, and set monitoring points on the slurry pump body.

[0012] Step 6: Solve step 4, respectively, and analyze the vibration characteristics and stress variation law of the bearing at the transmission end of the slurry pump without considering the deadweight of the bearing and considering the radial force generated by the deadweight of the bearing and other factors.

[0013] Step 7, solve step 5, only change the working condition of the inlet speed, and analyze the change law of the head, static pressure, flow rate and axial force generated by the fluid medium of the finite element model of the slurry pump in different health states.

[0014] Step 8. Apply the pump shaft axial force generated in step 7 to the transmission end bearing to achieve the coupling between the pump body and the transmission shaft bearing. Define the simulation time and simulation parameters, boundary conditions, solid materials, load conditions, vibration monitoring points and stress extractors of various bearing components in ANSYS-LSDyna.

[0015] Step 9. Solve step 8, analyze the vibration characteristics of the transmission bearing under the coupling of the pump shaft axial force, change the transmission bearings with different pump shaft axial forces and different fault types, and analyze the vibration characteristics and stress change laws of the transmission bearings under different health states.

[0016] Among them, the specific steps of step 1 include: the main structural parameters of the transmission bearing include detailed structural dimensions such as bearing rolling elements, inner and outer rings, retaining frames, slurry pump impeller dimensions, volute dimensions, front and rear cover plate diameters, number of blades, etc.; the dimensions of the fault model are respectively 2*1.5*1.5 for the fault outer ring and 0.5mm*0.5mm*2mm for the inner ring fault, and the faults are all established on the 30° inclined surface of the model. The inner and outer rings of the slurry pump bearing are stretched and cut, and the drawn three-dimensional model parts are assembled, and then the assembly is saved and exported as an xt file. The main flow-through parts of the slurry pump body are fault-cut, the impeller fault size is 0.8mm*3mm*2mm, and the fault point is at the middle end of the third blade. The volute fault size shape is trapezoidal, with an upper base of 7mm, a lower base of 10mm, and the other two sides of 11mm and 10mm respectively. The depth of 10mm simulates the impeller damage and the pitting wear failure of the flow channel in the volute, and the fault positions are all established on a 30° inclined plane.

[0017] The specific steps of step 2 include: giving the material of the slurry pump transmission bearing, then performing three-dimensional meshing, locally subdividing the contact surface, setting the inner ring of the bearing to rotate, fixing the outer ring, setting the load conditions and load conditions as well as the simulation time and the number of computing cores.

[0018] The specific steps of step 3 include: using the pre-processing module of space-claim to extract the fluid domain of the slurry pump body from the established 3D model of the slurry pump, and then using the ansys-icem module to mesh the slurry pump fluid domain, naming the interface and fluid area, establishing the finite element model of the slurry pump body and the finite element model of the transmission bearing, and exporting the fluid domain model, drawing sketches of different radial sections in the 3D software, and then using the point capture function in the sw 3D software to obtain the coordinates of the volute and each monitoring point in the 0°-270° direction of each circumferential direction. And record the coordinates of the intersection of different radial circles and two vertical lines, insert the point command in the Geometries in fluent, and establish the previously recorded monitoring point coordinates.

[0019] The specific steps of step 4 include: defining the materials of each bearing component, fixing the outer ring of the bearing, setting the inner ring to rotate, setting the simulation solution parameters including solution time, sampling frequency, number of solution cores, etc. Setting the extracted grid nodes, respectively extracting the vibration signals in the x, y, and z directions of the nodes and the equivalent stress of each bearing component.

[0020] Step 5 includes: defining the fluid medium material of the slurry pump, the turbulence model, the solution method and the correlation coefficient of the turbulence equation, and setting the inlet and outlet and various test reports and the lift calculation formula, simulation time and step size.

[0021] In the above step 4, when simulating the dynamics of the transmission bearing, the specific steps include: setting the materials of the various components of the bearing, fixing the outer ring of the bearing, setting the inner ring to rotate and applying radial load and bearing gravity parameters in the radial direction of the inner ring, setting the inner ring to be a rigid body, setting the simulation solution time, sampling frequency, and number of solution cores.

[0022] When simulating the pump fluid in step 5 above, the specific steps include: defining the fluid medium inside the pump, the speed of the pump, the inlet and outlet boundary conditions of the pump, establishing the monitoring points recorded in step 2 one by one in the fluent mesh model in the fluent model, and setting the simulation solution method, solution time and number of calculation cores. Define report-surface report-select the average pressure in the drop-down, set the monitoring report, and name it xxp and xxv, and also select the total pressure in the drop-down option, and then select the named inlet and outlet, and establish the inp and outp detection reports and head reports respectively. The head formula is H = (inp-outp) / ρg, where inp and outp are the total pressure of the inlet and outlet. The monitoring and recording function of the fluent software can be used to monitor the total pressure of the inlet and outlet. ρ is the density of the fluid medium, and its unit is kg / m3, g = 9.81m / s2. Then use the monitoring and recording function of the fluent software to edit the head formula. After the simulation is completed, you can click computer to calculate the head of the slurry pump. The lift of the slurry pump under different health conditions is plotted into a curve, and the pressure of the front and rear cover plates at the detection point along the 180° radial direction is averaged to calculate the axial force of the fluid medium. The axial force formula is: Where D 2 D is the diameter of the front cover. 1 is the diameter of the rear cover plate, p is the pressure value at the geometric center, and in order to more reasonably reflect the axial force, the pressure difference of the mean pressure at the geometric center of the front and rear cover plates is taken. As the pressure value of the geometric center ( It is the average value of the instantaneous pressure change in the third layer of 180° radial direction of the front and rear cover plates). The instantaneous pressure change recorded at the monitoring point is exported to a spreadsheet and the pressure difference of the average pressure of the front and rear cover plates in the third layer 180° direction is calculated as the pressure value at the geometric center, that is, Δp=p. Finally, the axial force is recorded and plotted into a curve, and the instantaneous pressure collected at 0°-270° on the volute is plotted as a pressure and velocity curve as it changes with time.

[0023] The specific steps of step 6 include: after the solution of step 4 is completed, statistics are collected and checked for changes in equivalent stress of each component of the transmission bearing in different health states and changes in vibration characteristics in different directions.

[0024] The specific steps of step 7 include: after the solution of step 5 is completed, the monitoring report data of each monitoring point is counted, the report data is imported into the spreadsheet and the axial force generated by the slurry pump fluid on the cover plate is calculated, and the pressure cloud map and velocity cloud map of the pump flow field can be viewed using CFD-post.

[0025] The specific steps of step 8 include: applying the axial force generated by the pump fluid calculated in step 7 to the transmission bearing to achieve the coupling between the pump and the transmission bearing, and then using ANSYS-LSDyna to change the load conditions of the transmission bearing, set the simulation time, solve the number of cores, inner and outer ring materials, inner ring rotation and outer ring fixed boundary conditions, vibration monitoring point settings, and stress extractor settings.

[0026] The specific steps of step 9 include: solving step 8, analyzing the vibration characteristics of the transmission bearing and the stress distribution of different parts of the transmission bearing, and statistically analyzing the stress distribution of the transmission bearing under different working conditions.

[0027] The present invention establishes finite element models of transmission bearings in different health states and finite element models of slurry pump bodies in different health states; uses ANSYS-LSDyna to simulate and analyze the vibration characteristics and stress distribution laws of transmission bearings in different health states, and uses Fluent to analyze the fluid pressure, speed change law and axial force generated by the fluid medium of the slurry pump body model in different health states; by changing the inlet speed parameter of the slurry pump, the slurry pump head and the pump shaft axial force generated by the fluid medium under different variables are calculated; the axial force generated by the fluid medium of the slurry pump with different fault types under different inlet speed conditions is analyzed through Fluent fluid simulation, and the vibration signal and stress distribution results of the transmission bearing under different axial forces are statistically analyzed; through the coupling simulation analysis of Fluent and ANSYS-LSDyna, the vibration characteristics and equivalent stress distribution laws of the axial force generated by the slurry pump body with different fault types on its transmission bearing are obtained. Compared with the prior art, the present invention can provide a new method for fault identification and diagnosis of slurry pumps, improve work efficiency and reduce production and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a flow chart of an embodiment of a method for simulating coupled dynamic faults of a slurry pump and a transmission bearing of the present invention;

[0029] Figure 2 The finite element model of the healthy transmission bearing of the present invention;

[0030] Figure 3 The finite element model of the transmission bearing with inner ring failure of the present invention;

[0031] Figure 4The finite element model of the transmission bearing with outer ring failure of the present invention;

[0032] Figure 5 The finite element model of the mixed fault transmission bearing of the present invention;

[0033] Figure 6 The finite element model of the healthy slurry pump body of the present invention;

[0034] Figure 7 It is the finite element model of the slurry pump body with volute failure of the present invention;

[0035] Figure 8 The finite element model of the pump body of the impeller failure slurry pump of the present invention;

[0036] Fig. 9 This is the finite element model of the mixed fault slurry pump body of the present invention. DETAILED DESCRIPTION

[0037] The present invention is further explained below in conjunction with the accompanying drawings and specific implementations. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0038] Reference Figure 1 The present invention discloses a method for simulating coupled dynamic faults of a slurry pump and a transmission bearing, comprising the following steps: Step 1: Referring to Figure 2-Figure 5 , Figure 2-Figure 5 The figure is a schematic diagram of the finite element model of the transmission bearing in different health states implemented by the present invention. The bearing material parameters are defined and the finite element model of the transmission bearing in different health states is established. The specific steps are: using ANSYS software to set the bearing material parameters according to the types of bearing parts and actual material parameters, including the bearing material engineering data module, and improving the parameters such as Poisson's Ratio, Solids Density, Shear Modulus, and Bulk Modulus.

[0039] Use the Geometry module of ansys-lsdyna to set the rolling element, inner and outer rings of the bearing to Gr15, and set the cage to Structural steel. Open meshsh to set the contact pair, including the friction contact between the inner and outer rings and the rolling element, and the contact friction between the rolling element and the cage. Insert frictional in contacts, and set the friction contact coefficients between the inner and outer rings and the rolling element, and between the rolling element and the cage. Take the bearing rolling element as the contact body, the inner and outer rings as the target body, the rolling element as the contact body, and the cage as the target body to simulate the contact between the inner and outer rings and the rolling element, and the friction rolling between the rolling element and the cage in the actual bearing operation.

[0040] After the above friction contact is set, set other parameters. Right-click ansys-ls-dyna→insert→fixed support to fix the outer ring, then insert→remote displacement to set a remote displacement to simulate the bearing rotation, and apply it to the surface of the inner ring of the bearing→Apply, then insert→hourglass control to prevent the mesh from being distorted. Then insert→Force acts on the center of the inner surface of the inner ring of the bearing and applies a radial force to simulate the influence of the bearing vibration factor and its own gravity on the dynamic characteristics of the bearing. In the analysis settings, set the number of solution cores, the solution time step, and the total time. In Mesh, insert the mesh method as tetrahedral mesh, insert three size adjustments, and perform local mesh refinement on the bearing rolling elements, the inner and outer rings of the bearing, and the retaining cage. Finally, click generating mesh to generate the mesh.

[0041] Insert nine node acquisition detectors in the three directions of directional deformation, directional velocity, and directional Acceleration in the solution information to simulate the sensor to collect the bearing vibration signal. Then insert equivalent stress in the solution, select each component to insert the equivalent stress, there are four groups of components in total, so insert 4 equivalent stresses. In addition, insert Contact normalstress to view the contact stress on the inner and outer surfaces. Compare the maximum stress σ of the transmission bearing under the rotational load with the allowable stress [σ] of the transmission bearing. If σ≤[σ], the transmission bearing meets the strength requirements. Then click Solve. The vibration information and stress information of the node can be obtained.

[0042] See attached Figure 6-Figure 9 The finite element model of the slurry pump body in different health states established for the present invention is as follows: drag a fluent module in ansys, import the slurry pump body assembly model in geometries, and then extract the fluid domain in the pre-processing software space-claim. The extraction steps are as follows:

[0043] (1) The front and rear covers are combined with the volute

[0044] First, merge the front and rear end covers with the volute, hide the impeller model after merging, and select the merge option to merge the front and rear cover plates with the volute respectively. After the merge is completed and checked, delete the front and rear cover plate models imported previously.

[0045] (2) Volume extraction

[0046] Select the "Body Extraction" option, select the previously merged "Merged Body", extract the model boundary line of the "Merged Body", select the boundary lines of the front and rear cover plates and the volute outlet boundary line respectively, and then click "Surface Selection" to select a flow passage surface of a body. Here, the inner surface of the volute outlet is selected. Then click "Finish" to see the preliminary extracted slurry pump fluid domain. After the extraction is completed, delete the previous "Merged Body" model.

[0047] (3) Volume pruning

[0048] After the previous steps, the entire fluid area is now a whole. Now display the previously hidden impeller model, then select the "Merge" tab and use the fluid domain of (2) as the overall model. Use the impeller as a tool to separate the overall fluid domain model. After separation, you can see that the previous fluid domain model in the model tree has been divided into multiple parts. Select each part to view it separately and delete the unnecessary fluid domains. Finally, delete the impeller to form a preliminary fluid domain model. At this time, the impeller water body is not separated from the volute, but only a cavity is formed between the impeller and the front and rear cover plates. Therefore, it is also necessary to separate the impeller water body from the volute water body.

[0049] (4) Secondary volume separation

[0050] Select the Separate Body option next to the "Merge" tab, select the volute body as the target geometry, and then select the impeller as the tool. At this time, the impeller and volute have been separated. Name the extracted fluid domain model and delete the previous assembly model.

[0051] (5) Inlet and outlet flow channel extension

[0052] The extracted inlet and outlet sections are appropriately extended. The purpose of extending the inlet and outlet ends is to prevent fluid backflow, which will cause errors in numerical calculations. The inlet and outlet sections of the fluid domain are extended to about 1.5 times the inlet and outlet diameters. Finally, the three-dimensional fluid domain models of normal, impeller failure, volute failure, and impeller and volute mixed failure were extracted respectively. The extracted fluid domain model is saved as a step file, then assembled in the three-dimensional software, and then the sketch function in the three-dimensional software is used to make five equally spaced circles on the front and rear covers of the pump body fluid domain, and 90° and 180° vertical lines are made at the center of the circle. The intersection points with the circle are named 0°, 90°, 180°, and 270° in clockwise order. A total of five layers are divided into equal intervals, and a total of ten layers are divided on the front and rear covers, all of which are distributed in contour lines. Similarly, in order to facilitate the detection of pressure fluctuations, monitoring points in four directions are also set on the volute, and the coordinates of the monitoring points are recorded. Then name the fluid domain model under the mesh module, including the outlet, inlet, impeller, volute, and water pipe.

[0053] Perform tetrahedral meshing on the entire fluid domain, and perform local meshing on the inlet, outlet, static and dynamic interface, and blades. Perform volume meshing on the impeller, volute, water body, and cover. After the mesh model is divided, click Update to update the mesh. After the update is successful, close the mesh module.

[0054] Double-click setup to open the Fluent fluid calculation setting interface. Set gravity and solver in Geometries, click material to set the fluid medium material, then click the inlet, right-click to change the inlet type to velocity inlet, and the outlet type to pressure outlet. Before setting the speed, first click unit to change the speed unit to r / min, then click the impeller to set its speed, check Frame Motion and then select the rotating coordinate axis in rotation-Axis. The coefficient of the rotating coordinate axis is 1, and the other coordinate systems default to zero. Set the relative rotation of the impeller wall, and its rotation speed is 0. Finally, in Geometries, the recorded coordinates of each monitoring point are established on the fluent grid model.

[0055] Click methods to set the solution method and convergence factor, set the turbulence model and wall equation in Models, and set the turbulence intensity and pressure coefficient of the turbulence equation, energy equation, and mass equation in Controls.

[0056] In Run calculation, set the final solution time, solution time substep, define the head and inlet and outlet pressures, the monitoring report of the speed change over time, and the report of each monitoring point. After clicking Save, the entire flow field is initialized, and then click Calculation to simulate the solution of the fluid flow field.

[0057] The output monitoring report data of each detection point is used to solve the axial force using the axial force formula mentioned above, and the detected head is calculated and recorded, and then the head is plotted as a curve along with the inlet speed.

[0058] Finally, the calculated pump shaft axial force is equivalently loaded onto the transmission bearing, and then the dynamic simulation analysis of the transmission bearings with different fault types is carried out to analyze the effects of different axial forces on the bearings, and the calculation results are statistically compared. The influence of the axial force generated by the fluid medium of the pump under different working conditions on the vibration law of the dynamic characteristics of its transmission bearing and the distribution law of the equivalent stress change are analyzed.

Claims

1. A slurry pump and transmission bearing coupled dynamic fault simulation method, characterized in that: Step 1: According to the parameters and dimensions of the slurry pump and its transmission bearing, a three-dimensional slurry model of impeller failure, volute failure, and mixed failure, as well as a three-dimensional solid model of the transmission bearing of inner ring failure, outer ring failure, and mixed failure are established. Step 2: Use the ANSYS-ICEM module to mesh the transmission bearings of the slurry pump in different health states and establish an explicit dynamic finite element model of the bearing. Step 3: Extract the fluid domain of the three-dimensional model of the slurry pump in different health states and name the fluid domain. Then, mesh the fluid domain model and establish a finite element model of the slurry pump. Step 4: Use the ANSYS-LSDynamic pre-processing module to perform explicit dynamic analysis on the transmission end bearing, define simulation parameters such as simulation time and boundary conditions, solid materials, load conditions, and set vibration monitoring points. Step 5: Use the fluent software to perform fluid mechanics analysis on the finite element model of the slurry pump in different health states, set the liquid medium and solution algorithm of the slurry pump, define other simulation parameters, and set monitoring points on the slurry pump body. Step 6: Solve step 4, respectively, and analyze the vibration characteristics and stress variation law of the bearing at the transmission end of the slurry pump without considering the deadweight of the bearing and considering the radial force generated by the deadweight of the bearing and other factors. Step 7, solve step 5, only change the working condition of the inlet speed, and analyze the change law of the head, static pressure, flow rate and axial force generated by the fluid medium of the finite element model of the slurry pump in different health states. Step 8. Apply the pump shaft axial force generated in step 7 to the transmission end bearing to achieve the coupling between the pump body and the transmission shaft bearing. Define the simulation time and simulation parameters, boundary conditions, solid materials, load conditions, and set the vibration monitoring points and stress extractors for each bearing component in ANSYS-LSDyna. Step 9, solve step 8, analyze the vibration characteristics of the transmission bearing under the coupling of the pump shaft axial force, change the transmission bearings with different pump shaft axial forces and different fault types, and analyze the vibration characteristics of the transmission bearings under different health states.

2. The method of establishing a transmission end bearing model in different health states and a slurry pump three-dimensional model in different health states as described in claim 1, characterized in that: The three-dimensional solid model of the transmission bearing and the three-dimensional solid model of the slurry pump are established. The main structural parameters of the transmission bearing include detailed structural dimensions of the bearing rolling elements, inner and outer rings, retaining frames, slurry pump impeller dimensions, volute dimensions, front and rear cover plate diameters, number of blades, etc.

3. The method for establishing the bearing explicit dynamics finite element model and the slurry pump fluid finite element model according to claim 1 is characterized in that: The physical parameters of the transmission bearing that need to be defined include: material, load, boundary conditions of the inner and outer rings of the bearing, and simulation parameters such as the number of calculation cores, calculation time and sampling frequency; the physical parameters of the slurry pump include; fluid medium, liquid viscosity, turbulence intensity; and the motion parameters of the slurry pump: impeller speed and the coordinate axis that needs to rotate.

4. According to claim 1, the vibration characteristic law and stress-strain variation law of the driving end bearing of the slurry pump are analyzed, characterized in that: Monitoring points are set to extract vibration signals in the x, y, and z directions, and stress distribution extractors are set for each component to analyze the vibration laws of transmission bearings in different health states under different load conditions, as well as the stress and strain laws of each bearing component.

5. The method for analyzing the head under different health conditions according to claim 1, characterized in that: By simulating different types of slurry pump failures, under the condition of only changing the inlet speed, the head changes with the inlet speed. The head formula is H = (inp-outp) / ρg, where inp and outp are the total inlet and outlet pressures. The monitoring and recording function of the fluent software can be used to monitor the total inlet and outlet pressures. ρ is the density of the fluid medium, and its unit is kg / m3, g = 9.81m / s2. Then use the monitoring and recording function of the fluent software to edit the head formula, wait for the software simulation to end, and click computer to calculate the head of the slurry pump, record the head of the slurry pump at different flow rates, and finally draw a curve to show the head change law of different health states.

6. According to claim 1, the pressure and flow field distribution law under different inlet speed conditions and different health states are analyzed, characterized in that: Use the post-processing module of Fluent to establish a display plane in the xz / yz plane, and finally display the pressure and velocity cloud maps in a certain proportion to observe the flow direction and flow trend of the fluid in the flow field.

7. The method of claim 1 for analyzing the variation of the axial force generated by the fluid medium of a slurry pump in different health states at different inlet flow rates, characterized in that: The magnitude of the axial force of the pump shaft can be calculated by setting monitoring points. The magnitude of the axial force of the pump shaft mainly comes from the pressure difference between the front and rear covers. Therefore, it is necessary to set four monitoring points at 0°, 90°, 180°, and 270° on the front and rear covers of the slurry pump. Draw a circle along the radial direction of the slurry pump, divide the pump body into five layers (excluding the four detection points in the volute direction), and divide the radial circle at equal intervals. The pressure value at the geometric center position along the radial direction of 180° is used as the fluid pressure of the axial force, and its formula is: Where D2 is the diameter of the front cover, D1 is the diameter of the rear cover, and p is the pressure value at the geometric center. In order to more reasonably reflect the axial force, the pressure difference of the mean pressure at the geometric center of the front and rear covers is taken. The mean pressure at the geometric center ( The average value of the instantaneous pressure change in the third layer of the front and rear cover plates in the radial direction of 180° is taken, and the pressure difference between the average values ​​of the pressure of the front and rear cover plates in the third layer in the direction of 180° is extracted as the pressure value at the geometric center, that is, Δp=p. Finally, the axial force is recorded and plotted into a curve to observe its change pattern with flow velocity.

8. According to claim 1, the axial force of the pump shaft generated in step 7 is applied to the transmission end bearing to achieve coupling between the pump body and the transmission bearing, characterized in that: In order to load the axial force calculated in step 7 onto the transmission end bearing equivalently, the original load conditions are changed, and then the node monitoring points are set to extract the speed, acceleration, displacement information of the transmission bearing and the stress extractors of different parts of the transmission bearing.

9. According to claim 1, the step 7 is to analyze the influence of the axial force generated by the fluid medium on the transmission bearing, characterized in that: Explicit dynamic analysis is performed on transmission bearings in different health states. The axial force of the pump shaft is changed, and the vibration characteristics and stress distribution of each component are analyzed through monitoring point extractors and stress extractors.

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